Substituted heterocyclic compounds and methods of use

ABSTRACT

The present invention relates to compounds having the general formula 
                 
 
or a pharmaceutically acceptable salt thereof. Also included is a method of prophylaxis or treatment of inflammation, rheumatoid arthritis, Pagets disease, osteoporosis, multiple myeloma, uveititis, acute or chronic myelogenous leukemia, pancreatic β cell destruction, osteoarthritis, rheumatoid spondylitis, gouty arthritis, inflammatory bowel disease, adult respiratory distress syndrome (ARDS), psoriasis, Crohn&#39;s disease, allergic rhinitis, ulcerative colitis, anaphylaxis, contact dermatitis, asthma, muscle degeneration, cachexia, Reiter&#39;s syndrome, type I diabetes, type II diabetes, bone resorption diseases, graft vs. host reaction, Alzheimer&#39;s disease, stroke, myocardial infarction, ischemia reperfusion injury, atherosclerosis, brain trauma, multiple sclerosis, cerebral malaria, sepsis, septic shock, toxic shock syndrome, fever, myalgias due to HIV-1, HIV-2, HIV-3, cytomegalovirus (CMV), influenza, adenovirus, the herpes viruses or herpes zoster infection in a mammal comprising administering an effective amount a compound as described above.

This application claims benefit of provisional application 60/409,176filed on Sep. 9, 2002.

BACKGROUND OF THE INVENTION

The present invention comprises a new class of compounds useful intreating diseases, such as TNF-α, IL-1β, IL-6 and/or IL-8 mediateddiseases and other maladies, such as pain and diabetes. In particular,the compounds of the invention are useful for the prophylaxis andtreatment of diseases or conditions involving inflammation. Thisinvention also relates to intermediates and processes useful in thepreparation of such compounds.

Interleukin-1 (IL-1) and Tumor Necrosis Factor α (TNF-α) areproinflammatory cytokines secreted by a variety of cells, includingmonocytes and macrophages, in response to many inflammatory stimuli(e.g., lipopolysaccharide—LPS) or external cellular stress (e.g.,osmotic shock and peroxide).

Elevated levels of TNF-α and/or IL-1 over basal levels have beenimplicated in mediating or exacerbating a number of disease statesincluding rheumatoid arthritis; Pagets disease; osteoporosis; multiplemyeloma; uveititis; acute and chronic myelogenous leukemia; pancreatic βcell destruction; osteoarthritis; rheumatoid spondylitis; goutyarthritis; inflammatory bowel disease; adult respiratory distresssyndrome (ARDS); psoriasis; Crohn's disease; allergic rhinitis;ulcerative colitis; anaphylaxis; contact dermatitis; asthma; muscledegeneration; cachexia; Reiter's syndrome; type I and type II diabetes;bone resorption diseases; graft vs. host reaction; ischemia reperfusioninjury; atherosclerosis; brain trauma; multiple sclerosis; cerebralmalaria; sepsis; septic shock; toxic shock syndrome; fever, and myalgiasdue to infection. HIV-1, HIV-2, HIV-3, cytomegalovirus (CMV), influenza,adenovirus, the herpes viruses (including HSV-1, HSV-2), and herpeszoster are also exacerbated by TNF-α.

It has been reported that TNF-α plays a role in head trauma, stroke, andischemia. For instance, in animal models of head trauma (rat), TNF-αlevels increased in the contused hemisphere (Shohami et al., J. Cereb.Blood Flow Metab. 14, 615 (1994)). In a rat model of ischemia whereinthe middle cerebral artery was occluded, the levels of TNF-α mRNA ofTNF-α increased (Feurstein et al., Neurosci. Lett. 164, 125 (1993)).Administration of TNF-α into the rat cortex has been reported to resultin significant neutrophil accumulation in capillaries and adherence insmall blood vessels. TNF-α promotes the infiltration of other cytokines(IL-1β, IL-6) and also chemokines, which promote neutrophil infiltrationinto the infarct area (Feurstein, Stroke 25, 1481 (1994)). TNF-α hasalso been implicated to play a role in type II diabetes (Endocrinol.130, 43-52, 1994; and Endocrinol. 136, 1474-1481, 1995).

TNF-α appears to play a role in promoting certain viral life cycles anddisease states associated with them. For instance, TNF-α secreted bymonocytes induced elevated levels of HIV expression in a chronicallyinfected T cell clone (Clouse et al., J. Immunol. 142, 431 (1989)).Lahdevirta et al., (Am. J. Med. 85, 289 (1988)) discussed the role ofTNF-α in the HIV associated states of cachexia and muscle degradation.

TNF-α is upstream in the cytokine cascade of inflammation. As a result,elevated levels of TNF-α may lead to elevated levels of otherinflammatory and proinflammatory cytokines, such as IL-1, IL-6, andIL-8.

Elevated levels of IL-1 over basal levels have been implicated inmediating or exacerbating a number of disease states includingrheumatoid arthritis; osteoarthritis; rheumatoid spondylitis; goutyarthritis; inflammatory bowel disease; adult respiratory distresssyndrome (ARDS); psoriasis; Crohn's disease; ulcerative colitis;anaphylaxis; muscle degeneration; cachexia; Reiter's syndrome; type Iand type II diabetes; bone resorption diseases; ischemia reperfusioninjury; atherosclerosis; brain trauma; multiple sclerosis; sepsis;septic shock; and toxic shock syndrome. Viruses sensitive to TNF-αinhibition, e.g., HIV-1, HIV-2, HIV-3, are also affected by IL-1.

TNF-α and IL-1 appear to play a role in pancreatic β cell destructionand diabetes. Pancreatic β cells produce insulin which helps mediateblood glucose homeostasis. Deterioration of pancreatic β cells oftenaccompanies type I diabetes. Pancreatic β cell functional abnormalitiesmay occur in patients with type II diabetes. Type II diabetes ischaracterized by a functional resistance to insulin. Further, type IIdiabetes is also often accompanied by elevated levels of plasma glucagonand increased rates of hepatic glucose production. Glucagon is aregulatory hormone that attenuates liver gluconeogenesis inhibition byinsulin. Glucagon receptors have been found in the liver, kidney andadipose tissue. Thus glucagon antagonists are useful for attenuatingplasma glucose levels (WO 97/16442, incorporated herein by reference inits entirety). By antagonizing the glucagon receptors, it is thoughtthat insulin responsiveness in the liver will improve, therebydecreasing gluconeogenesis and lowering the rate of hepatic glucoseproduction.

In rheumatoid arthritis models in animals, multiple intra-articularinjections of IL-1 have led to an acute and destructive form ofarthritis (Chandrasekhar et al., Clinical Immunol Immunopathol. 55, 382(1990)). In studies using cultured rheumatoid synovial cells, IL-1 is amore potent inducer of stromelysin than is TNF-α (Firestein, Am. J.Pathol. 140, 1309 (1992)). At sites of local injection, neutrophil,lymphocyte, and monocyte emigration has been observed. The emigration isattributed to the induction of chemokines (e.g., IL-8), and theup-regulation of adhesion molecules (Dinarello, Eur. Cytokine Netw. 5,517-531 (1994)).

IL-1 also appears to play a role in promoting certain viral life cycles.For example, cytokine-induced increase of HIV expression in achronically infected macrophage line has been associated with aconcomitant and selective increase in IL-1 production (Folks et al., J.Immunol. 136, 40 (1986)). Beutler et al. (J. Immunol. 135, 3969 (1985))discussed the role of IL-1 in cachexia. Baracos et al. (New Eng. J. Med.308, 553 (1983)) discussed the role of IL-1 in muscle degeneration.

In rheumatoid arthritis, both IL-1 and TNF-α induce synoviocytes andchondrocytes to produce collagenase and neutral proteases, which leadsto tissue destruction within the arthritic joints. In a model ofarthritis (collagen-induced arthritis (CIA) in rats and mice),intra-articular administration of TNF-α either prior to or after theinduction of CIA led to an accelerated onset of arthritis and a moresevere course of the disease (Brahn et al., Lymphokine Cytokine Res. 11,253 (1992); and Cooper, Clin. Exp. Immunol. 898, 244 (1992)).

IL-8 has been implicated in exacerbating and/or causing many diseasestates in which massive neutrophil infiltration into sites ofinflammation or injury (e.g., ischemia) is mediated by the chemotacticnature of IL-8, including, but not limited to, the following: asthma,inflammatory bowel disease, psoriasis, adult respiratory distresssyndrome, cardiac and renal reperfusion injury, thrombosis andglomerulonephritis. In addition to the chemotaxis effect on neutrophils,IL-8 also has the ability to activate neutrophils. Thus, reduction inIL-8 levels may lead to diminished neutrophil infiltration.

Several approaches have been taken to block the effect of TNF-α. Oneapproach involves using soluble receptors for TNF-α (e.g., TNFR-55 orTNFR-75), which have demonstrated efficacy in animal models ofTNF-α-mediated disease states. A second approach to neutralizing TNF-αusing a monoclonal antibody specific to TNF-α, cA2, has demonstratedimprovement in swollen joint count in a Phase II human trial ofrheumatoid arthritis (Feldmann et al., Immunological Reviews, pp.195-223 (1995)). These approaches block the effects of TNF-α and IL-1 byeither protein sequestration or receptor antagonism.

U.S. Pat. No. 5,100,897, incorporated herein by reference in itsentirety, describes pyrimidinone compounds useful as angiotensin IIantagonists wherein one of the pyrimidinone ring nitrogen atoms issubstituted with a substituted phenylmethyl or phenethyl radical.

U.S. Pat. No. 5,162,325, incorporated herein by reference in itsentirety, describes pyrimidinone compounds useful as angiotensin IIantagonists wherein one of the pyrimidinone ring nitrogen atoms issubstituted with a substituted phenylmethyl radical.

EP 481448, incorporated herein by reference in its entirety, describespyrimidinone compounds useful as angiotensin II antagonists wherein oneof the pyrimidinone ring nitrogen atoms is substituted with asubstituted phenyl, phenylmethyl or phenethyl radical.

CA 2,020,370, incorporated herein by reference in its entirety,describes pyrimidinone compounds useful as angiotensin II antagonistswherein one of the pyrimidinone ring nitrogen atoms is substituted witha substituted biphenylaliphatic hydrocarbon radical.

BRIEF DESCRIPTION OF THE INVENTION

The present invention comprises a new class of compounds useful in theprophylaxis and treatment of diseases, such as TNF-α, IL-1β, IL-6 and/orIL-8 mediated diseases and other maladies, such as pain and diabetes. Inparticular, the compounds of the invention are useful for theprophylaxis and treatment of diseases or conditions involvinginflammation. Accordingly, the invention also comprises pharmaceuticalcompositions comprising the compounds, methods for the prophylaxis andtreatment of TNF-α, IL-1β, IL-6 and/or IL-8 mediated diseases, such asinflammatory, pain and diabetes diseases, using the compounds andcompositions of the invention, and intermediates and processes usefulfor the preparation of the compounds of the invention.

The compounds of the invention are represented by the following generalstructure:

The foregoing merely summarizes certain aspects of the invention and isnot intended, nor should it be construed, as limiting the invention inany way. All patents and other publications recited herein are herebyincorporated by reference in their entirety.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the present invention, there is provided compounds ofthe formula:

or a pharmaceutically acceptable salt thereof, wherein

R¹ is H or C₁₋₈alkyl;

R² is C₁₋₈alkyl, phenyl, benzyl, R^(c), R^(f), C₁₋₄alkylR^(c),C₁₋₄alkylR^(f) or R^(g);

R³ is phenyl, naphthyl, or a saturated or unsaturated 5- or 6-memberedring heterocycle containing 1-4 heteroatoms selected from N, O and S,wherein no more than 2 of the heteroatoms are O or S, and theheterocycle is substituted by 0, 1 or 2 oxo groups and is optionallyfused with a benzo group, any of which are substituted by 0, 1, 2 or 3substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro,—C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a),—OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b),—OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b),—S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b),—S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a),—NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b),—N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a),—N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a),—NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a);

R⁴ is phenyl, naphthyl, or a saturated or unsaturated 5- or 6-memberedring heterocycle containing 1-4 heteroatoms selected from N, O and S,wherein no more than 2 of the heteroatoms are O or S, and theheterocycle is substituted by 0, 1 or 2 oxo groups and is optionallyfused with a benzo group, any of which are substituted by 0, 1, 2 or 3substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro,—C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a),—OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b),—OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b),—S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b),—S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a),—NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b),—N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a),—N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a),—NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a);

R^(a) is independently at each instance H or R^(b);

R^(b) is independently at each instance C₁₋₈alkyl, phenyl or benzyl;

R^(c) is independently at each instance a saturated or unsaturated 5-,6- or 7-membered monocyclic or 6-, 7-, 8-, 9-, 10- or 11-memberedbicyclic ring containing 1, 2 or 3 atoms selected from N, O and S,wherein the ring is fused with 0 or 1 benzo groups and 0 or 1 saturatedor unsaturated 5-, 6- or 7-membered heterocyclic ring containing 1, 2 or3 atoms selected from N, O and S; wherein the carbon atoms of the ringare substituted by 0, 1 or 2 oxo groups;

R^(d) is independently at each instance C₁₋₈alkyl, C₁₋₄haloalkyl, halo,cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a),—C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b) —OC(═O)NR^(a)R^(a),—OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a),—SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a),—S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b),—S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b),—N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a),—N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b),—N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) or—NR^(a)C₂₋₆alkylOR^(a);

R^(e) is independently at each instance C₁₋₆alkyl substituted by 1, 2 or3 substituents independently selected from R^(d);

R^(f) is independently at each instance R^(c) substituted by 1, 2 or 3substituents independently selected from R^(d); and

R^(g) is independently at each instance R^(b) substituted by 1, 2 or 3substituents independently selected from R^(c), R^(f) and R^(d).

In another embodiment, in conjunction with any of the above or belowembodiments, R¹ is H.

In another embodiment, in conjunction with any of the above or belowembodiments, the compound has the structure

wherein R¹ is C₁₋₈alkyl.

In another embodiment, in conjunction with any of the above or belowembodiments, the compound has the structure

wherein R¹ is C₁₋₈alkyl.

In another embodiment, in conjunction with any of the above or belowembodiments, R² is R^(c), R^(f), C₁₋₄alkylR^(c), C₁₋₄alkylR^(f) orR^(g).

In another embodiment, in conjunction with any of the above or belowembodiments, R² is R^(c).

In another embodiment, in conjunction with any of the above or belowembodiments, R² is C₁₋₄alkylR^(c).

In another embodiment, in conjunction with any of the above or belowembodiments, R² is C₁₋₄alkylR^(f).

In another embodiment, in conjunction with any of the above or belowembodiments, R² is R^(g).

In another embodiment, in conjunction with any of the above or belowembodiments, R² is C₁₋₈alkyl, phenyl or benzyl.

In another embodiment, in conjunction with any of the above or belowembodiments, R² is C₁₋₈alkyll.

In another embodiment, in conjunction with any of the above or belowembodiments, R² is phenyl or benzyl.

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is phenyl or naphthyl both of which are substituted by0, 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo,cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a),—C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a),—OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a),—SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a),—S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b),—S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b),—N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a),—N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b),—N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and—NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is unsubstituted naphthyl or phenyl substituted by 1, 2or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano,nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a),—C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a),—OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a),—SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a),—S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b),—S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b),—N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a),—N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b),—N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and—NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is unsubstituted naphthyl.

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is phenyl substituted by 1, 2 or 3 substituents selectedfrom C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b),—C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a),—OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b),—OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b),—S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b),—S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a),—NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b),—N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a),—N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a),—NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is phenyl substituted by 1, 2 or 3 substituents selectedfrom C₁₋₈alkyl, C₁₋₄haloalkyl, and halo.

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is phenyl substituted by 1 or 2 chlorine atoms.

In another embodiment, in conjunction with any of the above or belowembodiments, R³ is a saturated or unsaturated 5- or 6-membered ringheterocycle containing 1-4 heteroatoms selected from N, O and S, whereinno more than 2 of the heteroatoms are O or S, and the heterocycle issubstituted by 0, 1 or 2 oxo groups and is optionally fused with a benzogroup, any of which are substituted by 0, 1, 2 or 3 C₁₋₈alkyl,C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b),—C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b),—OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a),—OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b), —S(═O)₂R^(b),—S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b),—S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a),—NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b),—N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a),—N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a),—NR^(a)C₂₋₆alkylNR^(a)R^(a) or —NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is a saturated or unsaturated 5- or 6-membered ringheterocycle containing 1-4 heteroatoms selected from N, O and S, whereinno more than 2 of the heteroatoms are O or S, and the heterocycle issubstituted by 0, 1 or 2 oxo groups and is optionally fused with a benzogroup, any of which are substituted by 0, 1, 2 or 3 substituentsselected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b),—C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a),—OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b),—OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR², —SR^(a), —S(═O)R^(b),—S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b),—S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a),—NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b),—N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a),—N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a),—NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is an unsaturated 6-membered ring heterocycle containing1 or 2 N atoms, and the heterocycle is substituted by 0, 1, 2 or 3substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro,—C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a),—OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b),—OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b),—S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b),—S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a),—NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b),—N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a),—N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a),—NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is a an unsubstituted, unsaturated 6-membered ringheterocycle containing 1 or 2 N atoms.

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is pyridine.

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is pyrimidine.

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is phenyl or naphthyl, both of which are substituted by0, 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo,cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a),—C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a),—OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a),—SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a),—S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b),—S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b),—N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a),—N(R^(a))C(═NR^(a))NR^(a)R², —N(R^(a))S(═O)₂R^(b),—N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and—NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is pyridine or pyrimidine, both of which are substitutedby 0, 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl,halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a),—C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a),—OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a),—SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a),—S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b),—S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b),—N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a),—N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b),—N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and—NR^(a)C₂₋₆alkylOR^(a).

In another embodiment, in conjunction with any of the above or belowembodiments, R⁴ is not pyridine or phenyl.

Another aspect of the invention relates to a pharmaceutical compositioncomprising a compound according to any one of the above embodiments anda pharmaceutically acceptable carrier.

Another aspect of the invention relates to a method of prophylaxis ortreatment of inflammation comprising administering an effective amountof a compound according to any one of the above embodiments.

Another aspect of the invention relates to a method of prophylaxis ortreatment of rheumatoid arthritis, Pagets disease, osteoporosis,multiple myeloma, uveititis, acute or chronic myelogenous leukemia,pancreatic β cell destruction, osteoarthritis, rheumatoid spondylitis,gouty arthritis, inflammatory bowel disease, adult respiratory distresssyndrome (ARDS), psoriasis, Crohn's disease, allergic rhinitis,ulcerative colitis, anaphylaxis, contact dermatitis, asthma, muscledegeneration, cachexia, Reiter's syndrome, type I diabetes, type IIdiabetes, bone resorption diseases, graft vs. host reaction, Alzheimer'sdisease, stroke, myocardial infarction, ischemia reperfusion injury,atherosclerosis, brain trauma, multiple sclerosis, cerebral malaria,sepsis, septic shock, toxic shock syndrome, fever, myalgias due toHIV-1, HIV-2, HIV-3, cytomegalovirus (CMV), influenza, adenovirus, theherpes viruses or herpes zoster infection in a mammal comprisingadministering an effective amount of a compound according to any one ofthe above embodiments.

Another aspect of the invention relates to a method of lowering plasmaconcentrations of either or both TNF-α and IL-1 comprising administeringan effective amount of a compound according to any one of the aboveembodiments.

Another aspect of the invention relates to a method of lowering plasmaconcentrations of either or both IL-6 and IL-8 comprising administeringan effective amount of a compound according to any one of the aboveembodiments.

Another aspect of the invention relates to a method of prophylaxis ortreatment of diabetes disease in a mammal comprising administering aneffective amount of a compound according to any one of the aboveembodiments to produce a glucagon antagonist effect.

Another aspect of the invention relates to a method of prophylaxis ortreatment of a pain disorder in a mammal comprising administering aneffective amount of a compound according to any one of the aboveembodiments.

Another aspect of the invention relates to a method of decreasingprostaglandins production in a mammal comprising administering aneffective amount of a compound according to any one of the aboveembodiments.

Another aspect of the invention relates to a method of decreasingcyclooxygenase enzyme activity in a mammal comprising administering aneffective amount of a compound according to any one of the aboveembodiments. In another embodiment, the cyclooxygenase enzyme is COX-2.

Another aspect of the invention relates to a method of decreasingcyclooxygenase enzyme activity in a mammal comprising administering aneffective amount of the above pharmaceutical composition. In anotherembodiment the cyclooxygenase enzyme is COX-2.

Another aspect of the invention relates to the manufacture of amedicament comprising a compound according to any one of the aboveembodiments.

Another aspect of the invention relates to the manufacture of amedicament for the treatment of inflammation comprising administering aneffective amount of a compound according to any one of the aboveembodiments.

Another aspect of the invention relates to the manufacture of amedicament for the treatment of rheumatoid arthritis, Pagets disease,osteoporosis, multiple myeloma, uveititis, acute or chronic myelogenousleukemia, pancreatic β cell destruction, osteoarthritis, rheumatoidspondylitis, gouty arthritis, inflammatory bowel disease, adultrespiratory distress syndrome (ARDS), psoriasis, Crohn's disease,allergic rhinitis, ulcerative colitis, anaphylaxis, contact dermatitis,asthma, muscle degeneration, cachexia, Reiter's syndrome, type Idiabetes, type II diabetes, bone resorption diseases, graft vs. hostreaction, Alzheimer's disease, stroke, myocardial infarction, ischemiareperfusion injury, atherosclerosis, brain trauma, multiple sclerosis,cerebral malaria, sepsis, septic shock, toxic shock syndrome, fever,myalgias due to HIV-1, HIV-2, HIV-3, cytomegalovirus (CMV), influenza,adenovirus, the herpes viruses or herpes zoster infection in a mammalcomprising administering an effective amount of a compound according toany one of the above embodiments.

Another aspect of the invention relates to a method of making a compoundas described herein, comprising the steps of:

reacting R³—CO₂H with R⁴—C(═O)H in the presence of trialkylamine andacetic anhydride;

protecting the resulting acid with a protecting group; and

reacting the protected acid with hydrazine to form

The compounds of this invention may have in general several asymmetriccenters and are typically depicted in the form of racemic mixtures. Thisinvention is intended to encompass racemic mixtures, partially racemicmixtures and separate enantiomers and diasteromers.

The specification and claims contain listing of species using thelanguage “selected from . . . and . . . ” and “is . . . or . . . ”(sometimes referred to as Markush groups). When this language is used inthis application, unless otherwise stated it is meant to include thegroup as a whole, or any single members thereof, or any subgroupsthereof. The use of this language is merely for shorthand purposes andis not meant in any way to limit the removal of individual elements orsubgroups from the genus.

Unless otherwise specified, the following definitions apply to termsfound in the specification and claims:

“Aryl” means a phenyl or naphthyl radical, wherein the phenyl may befused with a C₃₋₄cycloalkyl bridge.

“Benzo group”, alone or in combination, means the divalent radicalC₄H₄═, one representation of which is —CH═CH—CH═CH—, that when vicinallyattached to another ring forms a benzene-like ring—for exampletetrahydronaphthylene, indole and the like.

“C_(α-β)alkyl” means an alkyl group comprising from α to β carbon atomsin a branched, cyclical or linear relationship or any combination of thethree. The alkyl groups described in this section may also containdouble or triple bonds. Examples of C₁₋₈alkyl include, but are notlimited to the following:

“Halogen” and “halo” mean a halogen atoms selected from F, Cl, Br and I.

“C_(α-β)haloalkyl” means an alkyl group, as described above, wherein anynumber—at least one—of the hydrogen atoms attached to the alkyl chainare replaced by F, Cl, Br or I.

“Heterocycle” means a ring comprising at least one carbon atom and atleast one other atom selected from N, O and S. Examples of heterocyclesthat may be found in the claims include, but are not limited to, thefollowing:

“Pharmaceutically-acceptable salt” means a salt prepared by conventionalmeans, and are well known by those skilled in the art. The“pharmacologically acceptable salts” include basic salts of inorganicand organic acids, including but not limited to hydrochloric acid,hydrobromic acid, sulfuric acid, phosphoric acid, methanesulphonic acid,ethanesulfonic acid, malic acid, acetic acid, oxalic acid, tartaricacid, citric acid, lactic acid, fumaric acid, succinic acid, maleicacid, salicylic acid, benzoic acid, phenylacetic acid, mandelic acid andthe like. When compounds of the invention include an acidic functionsuch as a carboxy group, then suitable pharmaceutically acceptablecation pairs for the carboxy group are well known to those skilled inthe art and include alkaline, alkaline earth, ammonium, quaternaryammonium cations and the like. For additional examples of“pharmacologically acceptable salts,” see infra and Berge et al., J.Pharm. Sci. 66:1 (1977).“Leaving group” generally refers to groups readily displaceable by anucleophile, such as an amine, a thiol or an alcohol nucleophile. Suchleaving groups are well known in the art. Examples of such leavinggroups include, but are not limited to, N-hydroxysuccinimide,N-hydroxybenzotriazole, halides, triflates, tosylates and the like.Preferred leaving groups are indicated herein where appropriate.“Protecting group” generally refers to groups well known in the artwhich are used to prevent selected reactive groups, such as carboxy,amino, hydroxy, mercapto and the like, from undergoing undesiredreactions, such as nucleophilic, electrophilic, oxidation, reduction andthe like. Preferred protecting groups are indicated herein whereappropriate. Examples of amino protecting groups include, but are notlimited to, aralkyl, substituted aralkyl, cycloalkenylalkyl andsubstituted cycloalkenyl alkyl, allyl, substituted allyl, acyl,alkoxycarbonyl, aralkoxycarbonyl, silyl and the like. Examples ofaralkyl include, but are not limited to, benzyl, ortho-methylbenzyl,trityl and benzhydryl, which can be optionally substituted with halogen,alkyl, alkoxy, hydroxy, nitro, acylamino, acyl and the like, and salts,such as phosphonium and ammonium salts. Examples of aryl groups includephenyl, naphthyl, indanyl, anthracenyl, 9-(9-phenylfluorenyl),phenanthrenyl, durenyl and the like. Examples of cycloalkenylalkyl orsubstituted cycloalkylenylalkyl radicals, preferably have 6-10 carbonatoms, include, but are not limited to, cyclohexenyl methyl and thelike. Suitable acyl, alkoxycarbonyl and aralkoxycarbonyl groups includebenzyloxycarbonyl, t-butoxycarbonyl, iso-butoxycarbonyl, benzoyl,substituted benzoyl, butyryl, acetyl, tri-fluoroacetyl, tri-chloroacetyl, phthaloyl and the like. A mixture of protecting groups can beused to protect the same amino group, such as a primary amino group canbe protected by both an aralkyl group and an aralkoxycarbonyl group.Amino protecting groups can also form a heterocyclic ring with thenitrogen to which they are attached, for example,1,2-bis(methylene)benzene, phthalimidyl, succinimidyl, maleimidyl andthe like and where these heterocyclic groups can further includeadjoining aryl and cycloalkyl rings. In addition, the heterocyclicgroups can be mono-, di- or tri-substituted, such as nitrophthalimidyl.Amino groups may also be protected against undesired reactions, such asoxidation, through the formation of an addition salt, such ashydrochloride, toluenesulfonic acid, trifluoroacetic acid and the like.Many of the amino protecting groups are also suitable for protectingcarboxy, hydroxy and mercapto groups. For example, aralkyl groups. Alkylgroups are also suitable groups for protecting hydroxy and mercaptogroups, such as tert-butyl.

Silyl protecting groups are silicon atoms optionally substituted by oneor more alkyl, aryl and aralkyl groups. Suitable silyl protecting groupsinclude, but are not limited to, trimethylsilyl, triethylsilyl,tri-isopropylsilyl, tert-butyldimethylsilyl, dimethylphenylsilyl,1,2-bis(dimethylsilyl)benzene, 1,2-bis(dimethylsilyl)ethane anddiphenylmethylsilyl. Silylation of an amino groups provide mono- ordi-silylamino groups. Silylation of aminoalcohol compounds can lead to aN,N,O-tri-silyl derivative. Removal of the silyl function from a silylether function is readily accomplished by treatment with, for example, ametal hydroxide or ammonium fluoride reagent, either as a discretereaction step or in situ during a reaction with the alcohol group.Suitable silylating agents are, for example, trimethylsilyl chloride,tert-butyl-dimethylsilyl chloride, phenyldimethylsilyl chloride,diphenylmethyl silyl chloride or their combination products withimidazole or DMF. Methods for silylation of amines and removal of silylprotecting groups are well known to those skilled in the art. Methods ofpreparation of these amine derivatives from corresponding amino acids,amino acid amides or amino acid esters are also well known to thoseskilled in the art of organic chemistry including amino acid/amino acidester or aminoalcohol chemistry.

Protecting groups are removed under conditions which will not affect theremaining portion of the molecule. These methods are well known in theart and include acid hydrolysis, hydrogenolysis and the like. Apreferred method involves removal of a protecting group, such as removalof a benzyloxycarbonyl group by hydrogenolysis utilizing palladium oncarbon in a suitable solvent system such as an alcohol, acetic acid, andthe like or mixtures thereof. A t-butoxycarbonyl protecting group can beremoved utilizing an inorganic or organic acid, such as HCl ortrifluoroacetic acid, in a suitable solvent system, such as dioxane ormethylene chloride. The resulting amino salt can readily be neutralizedto yield the free amine. Carboxy protecting group, such as methyl,ethyl, benzyl, tert-butyl, 4-methoxyphenylmethyl and the like, can beremoved under hydrolysis and hydrogenolysis conditions well known tothose skilled in the art.

It should be noted that compounds of the invention may contain groupsthat may exist in tautomeric forms, such as cyclic and acyclic amidineand guanidine groups, heteroatom substituted heteroaryl groups (Y′=O, S,NR), and the like, which are illustrated in the following examples:

and though one form is named, described, displayed and/or claimedherein, all the tautomeric forms are intended to be inherently includedin such name, description, display and/or claim.

Prodrugs of the compounds of this invention are also contemplated bythis invention. A prodrug is an active or inactive compound that ismodified chemically through in vivo physiological action, such ashydrolysis, metabolism and the like, into a compound of this inventionfollowing administration of the prodrug to a patient. The suitabilityand techniques involved in making and using prodrugs are well known bythose skilled in the art. For a general discussion of prodrugs involvingesters see Svensson and Tunek Drug Metabolism Reviews 165 (1988) andBundgaard Design of Prodrugs, Elsevier (1985). Examples of a maskedcarboxylate anion include a variety of esters, such as alkyl (forexample, methyl, ethyl), cycloalkyl (for example, cyclohexyl), aralkyl(for example, benzyl, p-methoxybenzyl), and alkylcarbonyloxyalkyl (forexample, pivaloyloxymethyl). Amines have been masked asarylcarbonyloxymethyl substituted derivatives which are cleaved byesterases in vivo releasing the free drug and formaldehyde (Bundgaard J.Med. Chem. 2503 (1989)). Also, drugs containing an acidic NH group, suchas imidazole, imide, indole and the like, have been masked withN-acyloxymethyl groups (Bundgaard Design of Prodrugs, Elsevier (1985)).Hydroxy groups have been masked as esters and ethers. EP 039,051 (Sloanand Little, Apr. 11, 1981) discloses Mannich-base hydroxamic acidprodrugs, their preparation and use.

“Cytokine” means a secreted protein that affects the functions of othercells, particularly as it relates to the modulation of interactionsbetween cells of the immune system or cells involved in the inflammatoryresponse. Examples of cytokines include but are not limited tointerleukin 1 (IL-1), preferably IL-1β, interleukin 6 (IL-6),interleukin 8 (IL-8) and TNF, preferably TNF-α (tumor necrosisfactor-α).“TNF, IL-1, IL-6, and/or IL-8 mediated disease or disease state” meansall disease states wherein TNF, IL-1, IL-6, and/or IL-8 plays a role,either directly as TNF, IL-1, IL-6, and/or IL-8 itself, or by TNF, IL-1,IL-6, and/or IL-8 inducing another cytokine to be released. For example,a disease state in which IL-1 plays a major role, but in which theproduction of or action of IL-1 is a result of TNF, would be consideredmediated by TNF.

Compounds according to the invention can be synthesized according to oneor more of the following methods. It should be noted that the generalprocedures are shown as it relates to preparation of compounds havingunspecified stereochemistry. However, such procedures are generallyapplicable to those compounds of a specific stereochemistry, e.g., wherethe stereochemistry about a group is (S) or (R). In addition, thecompounds having one stereochemistry (e.g., (R)) can often be utilizedto produce those having opposite stereochemistry (i.e., (S)) usingwell-known methods, for example, by inversion.

The following Examples are presented for illustrative purposes only andare not intended, nor should they be construed, as limiting theinvention in any manner. Those skilled in the art will appreciate thatmodifications and variations of the compounds disclosed herein can bemade without violating the spirit or scope of the present invention.

EXAMPLES Example 1

2-(4-Chloro-phenyl)-3-pyridin-4-yl-acrylic acid

To mixture of (4-Chloro-phenyl)-acetic acid 9.78 g andpyridine-4-carbaldehyde 6.14 g was added acetic anhydride 20 mL andtriethyl amine 20 mL. The reaction mixture was heated to 120° C. for 24hours and cooled down to room temperature. Water and ethyl acetate wereadded. The solids formed was filtered, washed with water and ethylacetate and dried to afford the title compound as a light yellow solid.MS (ES+): 260 (M+H)⁺.

Example 2

2-(4-Chloro-phenyl)-3-pyridin-4-yl-acrylic acid methyl ester

The solution of 2-(4-Chloro-phenyl)-3-pyridin-4-yl-acrylic acid 3.5 g inthionyl chloride 25 mL was heated to 70° C. for five hours. The reactionwas cooled to 0° C., then was added methanol 50 mL. After warm to roomtemperature over one hour, all the solvent removed under reducedpressure. Work up using ethyl acetate and sodium bicarbonate give thelight yellow solid. MS (ES+): 274 (M+H)⁺.

Example 3

4-(4-Chloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one

To a solution of 2-(4-Chloro-phenyl)-3-pyridin-4-yl-acrylic acid methylester 2.02 g in ethyl alcohol 25 mL was added hydrazine 2.37 g. Thereaction was heated to 50° C. for 135 minutes. All solvent was removedafter under reduced pressure to afford the title compound as lightyellow solid. MS (ES+): 274 (M+H)⁺.

Example 4

4-(4-Chloro-phenyl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

To solution of 4-(4-Chloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one 20mg in ethyl alcohol 5 mL was added Pd/C 1 mg. The reaction was heated to50° C. for 48 hours, cooled to room temperature, filtered andconcentrated to a solid. Purification by TLC plate followed bycrystallization from chloroform and methanol give the title compound asan off-white solid. MS (ES+): 272 (M+H)⁺.

Example 5

4-(4-Chloro-phenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

Step A:4-[4-(4-Chloro-phenyl)-3-oxo-5-pyridin-4-yl-pyrazolidin-1-yl]-piperidine-1-carboxylicacid tert-butyl ester

To a solution of 4-(4-Chloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one0.86 g and 4-Oxo-piperidine-1-carboxylic acid tert-butyl ester 0.75 g inchloroform 35 mL was added sodium triacetoxy boron hydride 0.75 g at 0°C., the reaction was warmed up to room temperature over two hours beforeheated to 50° C. for another two hours. The reaction was quenched withwater 25 mL at 0° C., and the organic layer was collected, filtered,dried over MgSO₄, concentrated to a yellow solid 0.42 g for beingdirectly used for next step. MS (ES+): 457 (M+H)⁺.

Step B:4-[4-(4-Chloro-phenyl)-3-oxo-5-pyridin-4-yl-2,3-dihydro-pyrazol-1-yl]-piperidine-1-carboxylicacid tert-butyl ester

To a solution of4-[4-(4-Chloro-phenyl)-3-oxo-5-pyridin-4-yl-pyrazolidin-1-yl]-piperidine-1-carboxylicacid tert-butyl ester 0.42 gin ethanol 25 mL was added palladium oncarbon 0.02 g. the reaction was heated to 50° C. for 48 hours. Thereaction was cooled to room temperature, filtered and concentrated.Purification by flash chromatography gave the title compound ascolorless oil. MS (ES+): 455 (M+H)⁺; (ES−): 453 (M−H).

Step C:4-(4-Chloro-phenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

To a solution of4-[4-(4-Chloro-phenyl)-3-oxo-5-pyridin-4-yl-2,3-dihydro-pyrazol-1-yl]-piperidine-1-carboxylicacid tert-butyl ester 200 mg in flask was added HCl in ether anddioxane. After 2.25 hours, the solvent was evaporated under reducedpressure to afford the title compound as yellow oil. MS (ES+): 355(M+H)⁺; (ES−): 353 (M−H).

Example 6

4-(4-Chloro-phenyl)-1-piperidin-3-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The title compound was analogously synthesized by the method describedin example 5 from 3-Oxo-piperidine-1-carboxylic acid tert-butyl ester.This compound was obtained as yellow solid. MS (ES+): 355 (M+H)⁺; (ES−):353 (M−H)⁻.

Example 7

4-(4-Chloro-phenyl)-1-piperidin-4-ylmethyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The title compound was analogously synthesized by the method describedin example 5 from 4-Formyl-piperidine-1-carboxylic acid tert-butylester. This compound was obtained as yellow solid. MS (ES+): 369 (M+H)⁺;(ES−): 367 (M−H)⁻.

Example 8

4-(4-Chloro-phenyl)-1-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The title compound was analogously synthesized by the method describedin example 5 from formaldehyde. This compound was obtained as yellowsolid. MS (ES+): 286 (M+H)⁺; (ES−): 284 (M−H)⁻.

Example 9

4-(3,4-Dichlorophenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The title compound was synthesized analogously by the method describedin Example 5. 3,4-Dichloro-phenylacetic acid, instead of4-chlorophenylacetic acid, was used. MS (ES+): 389.0 (M+H)⁺; (ES−):387.4 (M−H)⁻.

Example 10

4-(4-Chlorophenyl)-1-(1-methyl-piperidin-4-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

A solution of4-(4-chlorophenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one(0.12 g, 0.34 mmol) in anhydrous methanol (3 mL) was cooled to 0° C. inan ice-water bath and added formaldehyde (3 mL; 37 wt. % in water),followed by sodium borohydride (0.039 g, 1 mmol). After stirring for 1hour, the reaction was quenched with water and diluted with methylenechloride. The organic layer was washed with brine, dried (Na₂SO₄), andconcentrated in vacuo. The title compound was isolated as a yellowamorphous solid by preparative HPLC. MS (ES+): 369.2 (M+H)⁺; (ES−):367.1 (M−H)⁻.

Example 11

4-(4-Chlorophenyl)-1-(1-methyl-piperidin-3-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The title compound was synthesized analogously by the method describedin Example 10.4-(4-Chlorophenyl)-1-piperidin-3-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one,instead of4-(4-chlorophenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one,was used. MS (ES+): 369.2 (M+H)⁺; (ES−): 367.1 (M−H)⁻.

Example 12

4-(4-Chlorophenyl)-1-(1-isopropyl-piperidin-4-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The title compound was synthesized analogously by the method describedin Example 10. Acetone, instead of formaldehyde, was used. MS (ES+):397.3 (M+H)⁺; (ES−): 395.2 (M−H)⁻.

Example 13

4-[4-(4-Chlorophenyl)-3-methoxy-5-pyridin-4-yl-pyrazol-1-yl]-piperidine

Step A:4-[4-(4-Chlorophenyl)-3-methoxy-5-pyridin-4-yl-pyrazol-1-yl]-piperidine-1-carboxylicacid tert-butyl ester

A solution of4-[4-(4-chlorophenyl)-3-oxo-5-pyridin-4-yl-2,3-dihydro-pyrazol-1-yl]-piperidine-1-carboxylicacid tert-butyl ester (0.135 g, 0.3 mmol) in dry DMF (2 mL) was cooledto 0° C. and added lithium hydride (0.0035 g, 0.45 mmol). After stirringfor 5 minutes, iodomethane (0.037 mL, 0.6 mmol) was added and thereaction was allowed to gradually warmed to room temperature and stirredfor 20 hours. The reaction was diluted with ethyl acetate and washedwith water; the aqueous layer was back-washed with ethyl acetate. Thecombined organic layer was washed with brine, dried (Na₂SO₄), andconcentrated in vacuo. Flash chromatography with 1%, 3%, and 5%methanol/methylene chloride afforded 18.8 mg (13%) of a monomethylatedproduct. MS (ES+): 469.2 (M+H)⁺.

Step B:4-[4-(4-Chlorophenyl)-3-methoxy-5-pyridin-4-yl-pyrazol-1-yl]-piperidine

Following the procedure of Step C in Example 5, the title compound wasisolated as a yellow amorphous solid. MS (ES+): 369.2 (M+H)⁺.

Example 14

4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one

Step A: 3-(3,4-Dichloro-phenyl)-2-oxo-4-pyridin-4-yl-but-3-enoic acid

To mixture of (3,4-diChloro-phenyl)-acetic acid 10.3 g andpyridine-4-carbaldehyde 5.25 mL was added acetic anhydride 6 mL andpyridine 6 mL. The reaction mixture was heated to 120° C. for 2 hoursand cooled down to room temperature. Water and ethyl acetate were added.The solid formed was filtered, washed with water and ethyl acetate anddried to afford the title compound 10.2 g as a light yellow solid. MS(ES+): 292 (M+H)⁺.

Step B: 3-(3,4-Dichloro-phenyl)-2-oxo-4-pyridin-4-yl-but-3-enoic acidethyl ester

The solution of 3-(3,4-Dichloro-phenyl)-2-oxo-4-pyridin-4-yl-but-3-enoicacid 9.6 g in thionyl chloride 20 mL was heated to 80° C. for 1 hours.Vacuumed down the excess thionyl chloride, cooled to 0° C., then addedmethanol 50 mL. After warmed to room temperature over one hour and 60°C. for 1 h, all the solvent removed under reduced pressure. Work upusing ethyl acetate and sodium bicarbonate give the title compound 11.43g as white solid. MS (ES+): 322 (M+H)⁺.

Step C: 4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one

To a solution of3-(3,4-Dichloro-phenyl)-2-oxo-4-pyridin-4-yl-but-3-enoic acid ethylester 11.4 g in ethyl alcohol 50 mL was added hydrazine 1.68 mL. Thereaction was heated to 50° C. for 15 hours. All solvent was removedafter under reduced pressure to afford the title compound 10.8 g aslight yellow solid. MS (ES+): 308 (M+H)⁺.

Example 15

4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The solution of 4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one0.30 g, 20 mg Pd/C and 20 mL methanol was stirred at room temperature.Air was bubbled through for 2 hours. Filtered off the Pd/C catalyst,vacuumed down all solvent. The title compound was obtained as whitesolid 0.29 g. MS (ES+): 306 (M+H)⁺.

Example 16

4-(3,4-Dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

Step A:4-(3,4-Dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-pyrazolidin-3-one

To a solution of4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one 0.30 g and 0.11mL acetone in chloroform 20 mL was added NaBH₃(CN) 0.1 g at 0° C., thereaction was warmed 50° C. and stirred for 1 hour. The reaction wasquenched with sat.NaHCO₃ 25 mL at 0° C. The reaction mixture wasextracted with dichloromethane, 3×50 mL. The combined organic phase waswashed with brine, dried over anhydrous Na₂SO₄. After purification byflash chromatography, the title compound was obtained as yellow solid0.26 g. MS (ES+): 350 (M+H)⁺.

Step B:4-(3,4-Dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The solution of4-(3,4-Dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-pyrazolidin-3-one 90mg in dichloromethane 10 mL was treated with phenyltriethylammoniumtribromide 0.1 g at room temperature, The reaction mixture was stirredat room temperature for 15 h. The reaction was quenched with sat. Na₂SO₃25 mL at 0° C. The reaction mixture was extracted with dichloromethane,3×50 mL. The combined organic phase was washed with brine, dried overanhydrous Na₂SO₄. After purification by flash chromatography, the titlecompound was obtained as light yellow solid 45 mg. MS (ES+): 348 (M+H)⁺.

Example 17

4-(3,4-Dichloro-phenyl)-1-isopropyl-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

Step A:4-(3,4-Dichloro-phenyl)-1-isopropyl-2-methyl-5-pyridin-4-yl-pyrazolidin-3-one

In a 100 mL round bottom flask, was added 0.1 g4-(3,4-Dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-pyrazolidin-3-one and10 mL THF, stirred at 0° C. under nitrogen. 0.43 mL 1 M LHMDS in THF wasadded drop wise. After stirred at 0° C. for 30 min 0.026 mL iodomethanewas added drop wise. The resulted mixture was stirred from 0° C. to rtfor 2 hours, quenched with 20 mL sat. NH₄Cl, extracted withdichloromethane 3×25 mL. The organic phase was dried over anhydrousNa₂SO₄. After purification by flash chromatography, obtained the titlecompound 80 mg as light solid. MS (ES+): 364 (M+H)⁺.

Step B:4-(3,4-Dichloro-phenyl)-1-isopropyl-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The solution of4-(3,4-Dichloro-phenyl)-1-isopropyl-2-methyl-5-pyridin-4-yl-pyrazolidin-3-one40 mg in dichloromethane 10 mL was treated with phenyltriethylammoniumtribromide 0.1 g at room temperature, The reaction mixture was stirredat room temperature for 15 h. The reaction was quenched with sat. Na₂SO₃25 mL at 0° C. The reaction mixture was extracted with dichloromethane,3×25 mL. The combined organic phase was washed with brine, dried overanhydrous Na₂SO₄. After purification by flash chromatography, the titlecompound was obtained as light yellow solid 20 mg. MS (ES+): 362 (M+H)⁺.

Example 18

4-(3,4-Dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1-pyridin-3-ylmethyl-1,2-dihydro-pyrazol-3-one

Step A:4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-1-pyridin-3-ylmethyl-pyrazolidin-3-one

To a solution of4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one 0.30 g and 0.12mL 3-pyridinecarboxaldehyde in chloroform 20 mL was added NaBH₃(CN) 0.1g at 0° C., the reaction was warmed 50° C. and stirred for 1 hour. Thereaction was quenched with sat.NaHCO₃ 25 mL at 0° C. The reactionmixture was extracted with dichloromethane, 3×50 mL. The combinedorganic phase was washed with brine, dried over anhydrous Na₂SO₄. Afterpurification by flash chromatography, the title compound was obtained asyellow solid 0.28 g. MS (ES+): 399 (M+H)⁺.

Step B:4-(3,4-Dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1-pyridin-3-ylmethyl-pyrazolidin-3-oneand4-(3,4-Dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1-pyridin-3-ylmethyl-1,2-dihydro-pyrazol-3-one

In a 100 mL round bottom flask, was added 70 mg4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-1-pyridin-3-ylmethyl-pyrazolidin-3-oneand 10 mL THF, stirred at 0° C. under nitrogen. 0.26 mL 1 M LHMDS in THFwas added drop wise. After stirred at 0° C. for 30 min. 0.017 mLiodomethane was added drop wise. The resulted mixture was stirred from0° C. to rt for 2 hour, quenched with 20 mL sat. NH₄Cl, extracted withdichloromethane 3×25 mL. The crude MS showed the desired4-(3,4-Dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1-pyridin-3-ylmethyl-pyrazolidin-3-onewas there, MS (ES+): 413 (M+H)⁺. The organic phase was dried overanhydrous Na₂SO4. After purification by flash chromatography, the4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-1-pyridin-3-ylmethyl-pyrazolidin-3-onewas oxidized on column and obtained the4-(3,4-Dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1-pyridin-3-ylmethyl-1,2-dihydro-pyrazol-3-one12 mg as light yellow solid. MS (ES+): 411 (M+H)⁺.

Example 19

1-Cyclohexylmethyl-4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

Step A:1-Cyclohexylmethyl-4-(3,4-dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one

To a solution of4-(3,4-Dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-one 0.30 g and 0.2mL cyclohexanecarbaldehyde in chloroform 20 mL was added NaBH₃(CN) 0.1 gat 0° C., the reaction was warmed 50° C. and stirred for 1 hour. Thereaction was quenched with sat.NaHCO₃ 25 mL at 0° C. The reactionmixture was extracted with dichloromethane, 3×50 mL. The combinedorganic phase was washed with brine, dried over anhydrous Na₂SO₄. Afterpurification by flash chromatography, the title compound was obtained asyellow solid 0.4 g. MS (ES+): 404 (M+H)⁺.

Step B:1-Cyclohexylmethyl-4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-pyrazolidin-3-one

In a 100 mL round bottom flask, was added 0.4 g1-Cyclohexylmethyl-4-(3,4-dichloro-phenyl)-5-pyridin-4-yl-pyrazolidin-3-oneand 20 mL THF, stirred at 0° C. under nitrogen. 1.32 mL 1 M LHMDS in THFwas added drop wise. After stirred at 0° C. for 30 min. 0.11 mLiodomethane was added drop wise. The resulted mixture was stirred from0° C. to rt for 2 hour, quenched with 50 mL sat. NH₄Cl, extracted withdichloromethane 3×25 mL. The organic phase was dried over anhydrousNa₂SO₄. After purification by flash chromatography, obtained the titlecompound 0.4 g as light solid. MS (ES+): 418 (M+H)⁺.

Step C:1-Cyclohexylmethyl-4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one

The solution of1-Cyclohexylmethyl-4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-pyrazolidin-3-one0.16 g in toluene 20 mL and DMF 2 mL was treated withphenyltriethylammonium tribromide 0.22 g at room temperature, Thereaction mixture was refluxed for 4 h. The reaction was quenched withsat. Na₂SO₃ 25 mL at 0° C. The reaction mixture was extracted withdichloromethane, 3×25 mL. The combined organic phase was washed withbrine, dried over anhydrous Na₂SO₄. After purification by flashchromatography, the title compound was obtained as light yellow solid 80mg. MS (ES+): 416 (M+H)⁺.

Example 20

1-(4-Aminocyclohexyl)-4-(4-chlorophenyl)-5-pyridin-4-yl-1,2-dihydropyrazol-3-one

Step A:{4-[4-(4-Chlorophenyl)-3-oxo-5-pyridin-4-yl-2,3-dihydropyrazol-1-yl]cyclohexyl}carbamicacid tert-butyl ester

Following the procedure of Step A in Example 5, except substituting4-oxo-piperidine-1-carboxylic acid tert-butyl ester with(4-oxo-cyclohexyl)carbamic acid tert-butyl ester, the title compound wasprepared as an off-white amorphous solid. MS (ES+): 469.2 (M+H)⁺; (ES−):467.3 (M−H)⁻.

Step B:1-(4-Aminocyclohexyl)-4-(4-chlorophenyl)-5-pyridin-4-yl-1,2-dihydropyrazol-3-one

Following the procedure of Step C in Example 5, except substituting4-[4-(4-chlorophenyl)-3-oxo-5-pyridin-4-yl-2,3-dihydro-pyrazol-1-yl]-piperidine-1-carboxylicacid tert-butyl ester with{4-[4-(4-chlorophenyl)-3-oxo-5-pyridin-4-yl-2,3-dihydropyrazol-1-yl]cyclohexyl}carbamicacid tert-butyl ester, the title compound was prepared as a yellowamorphous solid. MS (ES+): 369.3 (M+H)⁺; (ES−): 367.2 (M−H)⁻.

Example 21

1-(4-Aminocyclohexyl)-4-napthalen-2-yl-5-pyridin-4-yl-1,2-dihydropyrazol-3-one

The title compound was synthesized analogously by the method describedin Example 20. Naphthalen-2-yl acetic acid, instead of(4-chlorophenyl)acetic acid, was used. MS (ES+): 385.2 (M+H)⁺; (ES−):383.3 (M−H)⁻.

Example 22

4-Naphthalen-2-yl-1-(3-phenylpropyl)-5-pyridin-4-1,2-dihydropyrazol-3-one

The title compound was synthesized analogously by the method describedin Step A, Example 20. 3-Phenylpropionaldehyde, instead of4-oxo-piperidine-1-carboxylic acid tert-butyl ester, was used. MS (ES+):390.2 (M+H)⁺; (ES−): 388.2 (M−H)⁻.

Biological Assays

The following assays were used to characterize the ability of compoundsof the invention to inhibit the production of TNF-α and IL-1-β. Thesecond assay can be used to measure the inhibition of TNF-α and/orIL-1-β in mice after oral administration of the test compounds. Thethird assay, a glucagon binding inhibition in vitro assay, can be usedto characterize the ability of compounds of the invention to inhibitglucagon binding. The fourth assay, a cyclooxygenase enzyme (COX-1 andCOX-2) inhibition activity in vitro assay, can be used to characterizethe ability of compounds of the invention to inhibit COX-1 and/or COX-2.The fifth assay, a Raf-kinase inhibition assay, can be used tocharacterize the compounds of the invention to inhibit phosphorylationof MEK by activated Raf-kinase.

Lipopolysaccharide-Activated Monocyte TNF Production Assay

Isolation of Monocytes

Test compounds were evaluated in vitro for the ability to inhibit theproduction of TNF by monocytes activated with bacteriallipopolysaccharide (LPS). Fresh residual source leukocytes (a byproductof plateletpheresis) were obtained from a local blood bank, andperipheral blood mononuclear cells (PBMCs) were isolated by densitygradient centrifugation on Ficol-Paque Plus (Pharmacia). PBMCs weresuspended at 2×10⁶/mL in DMEM supplemented to contain 2% FCS, 10 mM, 0.3mg/mL glutamate, 100 U/mL penicillin G and 100 mg/mL streptomycinsulfate (complete media). Cells were plated into Falcon flat bottom, 96well culture plates (200 μL/well) and cultured overnight at 37° C. and6% CO₂. Non-adherent cells were removed by washing with 200 μl/well offresh medium. Wells containing adherent cells (˜70% monocytes) werereplenished with 100 μL of fresh medium.

Preparation of Test Compound Stock Solutions

Test compounds were dissolved in DMZ. Compound stock solutions wereprepared to an initial concentration of 10-50 μM. Stocks were dilutedinitially to 20-200 μM in complete media. Nine two-fold serial dilutionsof each compound were then prepared in complete medium.

Treatment of Cells with Test Compounds and Activation of TNF Productionwith Lipopolysaccharide

One hundred microliters of each test compound dilution were added tomicrotiter wells containing adherent monocytes and 100 μL completemedium. Monocytes were cultured with test compounds for 60 min at whichtime 25 μL of complete medium containing 30 ng/mL lipopolysaccharidefrom E. coli K532 were added to each well. Cells were cultured anadditional 4 hrs. Culture supernatants were then removed and TNFpresence in the supernatants was quantified using an ELISA.

TNF ELISA

Flat bottom, 96 well Corning High Binding ELISA plates were coatedovernight (4° C.) with 150 μL/well of 3 μg/mL murine anti-human TNF-αMAb (R&D Systems #MAB210). Wells were then blocked for 1 h at roomtemperature with 200 μL/well of CaCl₂-free ELISA buffer supplemented tocontain 20 mg/mL BSA (standard ELISA buffer: 20 mM, 150 mM NaCl, 2 mMCaCl₂, 0.15 mM thimerosal, pH 7.4). Plates were washed and replenishedwith 100 μL of test supernatants (diluted 1:3) or standards. Standardsconsisted of eleven 1.5-fold serial dilutions from a stock of 1 ng/mLrecombinant human TNF (R&D Systems). Plates were incubated at roomtemperature for 1 h on orbital shaker (300 rpm), washed and replenishedwith 100 μL/well of 0.5 μg/mL goat anti-human TNF-α (R&D systems#AB-210-NA) biotinylated at a 4:1 ratio. Plates were incubated for 40min, washed and replenished with 100 μL/well of alkalinephosphatase-conjugated streptavidin (Jackson ImmunoResearch#016-050-084) at 0.02 μg/mL. Plates were incubated 30 min, washed andreplenished with 200 μL/well of 1 mg/mL of p-nitrophenyl phosphate.After 30 min, plates were read at 405 nm on a V_(max) plate reader.

Data Analysis

Standard curve data were fit to a second order polynomial and unknownTNF-α concentrations determined from their OD by solving this equationfor concentration. TNF concentrations were then plotted vs. testcompound concentration using a second order polynomial. This equationwas then used to calculate the concentration of test compounds causing a50% reduction in TNF production.

Compounds of the invention can also be shown to inhibit LPS-inducedrelease of IL-1 B, IL-6 and/or IL-8 from monocytes by measuringconcentrations of IL-1, IL-6 and/or IL-8 by methods well known to thoseskilled in the art. In a similar manner to the above described assayinvolving the LPS induced release of TNF-α from monocytes, compounds ofthis invention can also be shown to inhibit LPS induced release ofIL-1β, IL-6 and/or IL-8 from monocytes by measuring concentrations ofIL-1β, L-6 and/or IL-8 by methods well known to those skilled in theart. Thus, the compounds of the invention may lower elevated levels ofTNF-α, IL-1, IL-6, and IL-8 levels. Reducing elevated levels of theseinflammatory cytokines to basal levels or below is favorable incontrolling, slowing progression, and alleviating many disease states.All of the compounds are useful in the methods of treating diseasestates in which TNF-α, IL-1β, IL-6, and IL-8 play a role to the fullextent of the definition of TNF-α-mediated diseases described herein.

Lipopolysaccharide-Activated THP1 Cell TNF Production Assay

THP1 cells are resuspended in fresh THP1 media (RPMI 1640, 10%heat-inactivated FBS, 1×PGS, 1×NEAA, plus 30 μM βME) at a concentrationof 1E6/mL. One hundred microliters of cells per well are plated in apolystyrene 96-well tissue culture. One microgram per mL of bacterialLPS is prepared in THP1 media and is transferred to the wells. Testcompounds are dissolved in 100% DMSO and are serially diluted 3 fold ina polypropylene 96-well microtiter plate (drug plate). HI control and LOcontrol wells contain only DMSO. One microliter of test compound fromthe drug plate followed by 10 μL of LPS are transferred to the cellplate. The treated cells are induced to synthesize and secrete TNF-α at37° C. for 3 h. Forty microliters of conditioned media are transferredto a 96-well polypropylene plate containing 110 μL of ECL buffer (50 mMTris-HCl pH 8.0, 100 mM NaCl, 0.05% Tween 20, 0.05% NaN₃ and 1% FBS)supplemented with 0.44 nM MAB610 monoclonal Ab (R&D Systems), 0.34 nMruthenylated AF210NA polyclonal Ab (R&D Systems) and 44 μg/mL sheepanti-mouse M280 Dynabeads (Dynal). After a 2 h incubation at roomtemperature with shaking, the reaction is read on the ECL M8 Instrument(IGEN Inc.). A low voltage is applied to the ruthenylated TNF-α: immunecomplexes, which in the presence of TPA (the active component inOriglo), results in a cyclical redox reaction generating light at 620nM. The amount of secreted TNF-α in the presence of compound comparedwith that in the presence of DMSO vehicle alone (HI control) iscalculated using the formula: % control (POC)=(cpd−average LO)/(averageHI−average LO)*100. Data (consisting of POC and inhibitor concentrationin AM) is fitted to a 4-parameter equation (y=A+((B−A)/(1+((x/C)^D))),where A is the minimum y (POC) value, B is the maximum y (POC), C is thex (cpd concentration) at the point of inflection and D is the slopefactor) using a Levenburg-Marquardt non-linear regression algorithm.

The following compounds exhibit activities in the THP1 cell assay (LPSinduced TNF release) with IC₅₀ values of 20 μM or less:

-   4-(4-chloro-phenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(4-chloro-phenyl)-1-piperidin-3-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(4-chlorophenyl)-1-(1-methyl-piperidin-4-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(4-chlorophenyl)-1-(1-methyl-piperidin-3-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(4-chlorophenyl)-1-(1-isopropyl-piperidin-4-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(3,4-dichloro-phenyl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(3,4-dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   4-(3,4-dichloro-phenyl)-1-isopropyl-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;-   1-cyclohexylmethyl-4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one;    and-   1-(4-aminocyclohexyl)-4-(4-chlorophenyl)-5-pyridin-4-yl-1,2-dihydropyrazol-3-one.    Inhibition of LPS-Induced TNF-α Production in Mice

Male DBA/1LACJ mice are dosed with vehicle or test compounds in avehicle (the vehicle consisting of 0.5% tragacanth in 0.03 N HCl) 30minutes prior to lipopolysaccharide (2 mg/Kg, I.V.) injection. Ninetyminutes after LPS injection, blood is collected and the serum isanalyzed by ELISA for TNF-α levels.

Compounds of the invention may be shown to have anti-inflammatoryproperties in animal models of inflammation, including carrageenan pawedema, collagen induced arthritis and adjuvant arthritis, such as thecarrageenan paw edema model (C. A. Winter et al Proc. Soc. Exp. Biol.Med. (1962) vol 111, p 544; K. F. Swingle, in R. A. Scherrer and M. W.Whitehouse, Eds., Anti-inflammatory Agents, Chemistry and Pharmacology,Vol. 13-II, Academic, New York, 1974, p. 33) and collagen inducedarthritis (D. E. Trentham et al J. Exp. Med. (1977) vol. 146, p 857; J.S. Courtenay, Nature (New Biol.) (1980), Vol 283, p 666).

¹²⁵I-Glucagon Binding Screen with CHO/hGLUR Cells

The assay is described in WO 97/16442, which is incorporated herein byreference in its entirety.

Reagents

The reagents can be prepared as follows: (a) prepare fresh 1Mo-Phenanthroline (Aldrich) (198.2 mg/mL ethanol); (b) prepare fresh 0.5MDTT (Sigma); (c) Protease Inhibitor Mix (1000×): 5 mg leupeptin, 10 mgbenzamidine, 40 mg bacitracin and 5 mg soybean trypsin inhibitor per mLDMSO and store aliquots at −20° C.; (d) 250 μM human glucagon(Peninsula): solubilize 0.5 mg vial in 575 μl 0.1N acetic acid (1 μLyields 1 μM final concentration in assay for non-specific binding) andstore in aliquots at −20° C.; (e) Assay Buffer: 20 mM Tris (pH 7.8), 1mM DTT and 3 mM o-phenanthroline; (f) Assay Buffer with 0.1% BSA (fordilution of label only; 0.01% final in assay): 10 μL 10% BSA(heat-inactivated) and 990 μL Assay Buffer; (g) ¹²⁵I-Glucagon (NEN,receptor-grade, 2200 Ci/mmol): dilute to 50,000 cpm/25 μL in assaybuffer with BSA (about 50 pM final concentration in assay).

Harvesting of CHO/hGLUR Cells for Assay

1. Remove media from confluent flask then rinse once each with PBS (Ca,Mg-free) and Enzyme-free Dissociation Fluid (Specialty Media, Inc.).

2. Add 10 mL Enzyme-free Dissoc. Fluid and hold for about 4 min at 37°C.

3. Gently tap cells free, triturate, take aliquot for counting andcentrifuge remainder for 5 min at 1000 rpm.

4. Resuspend pellet in Assay Buffer at 75000 cells per 100 μL.

Membrane preparations of CHO/hGLUR cells can be used in place of wholecells at the same assay volume. Final protein concentration of amembrane preparation is determined on a per batch basis.

Assay

The determination of inhibition of glucagon binding can be carried outby measuring the reduction of I¹²⁵-glucagon binding in the presence ofcompounds of Formula I. The reagents are combined as follows:

Compound/ 250 μM CHO/hGLUR Vehicle Glucagon ¹²⁵I-Glucagon Cells Total—/5 μL — 25 μL 100 μL Binding + Com- 5 μL/— — 25 μL 100 μL pound Non-—/5 μL 1 μL 25 μL 100 μL specific BindingThe mixture is incubated for 60 min at 22° C. on a shaker at 275 rpm.The mixture is filtered over pre-soaked (0.5% polyethylimine (PEI)) GF/Cfiltermat using an Innotech Harvester or Tomtec Harvester with fourwashes of ice-cold 20 mM Tris buffer (pH 7.8). The radioactivity in thefilters is determined by a gamma-scintillation counter.

Thus, compounds of the invention may also be shown to inhibit thebinding of glucagon to glucagon receptors.

Cyclooxygenase Enzyme Activity Assay

The human monocytic leukemia cell line, THP-1, differentiated byexposure to phorbol esters expresses only COX-1; the human osteosarcomacell line 143B expresses predominantly COX-2. THP-1 cells are routinelycultured in RPMI complete media supplemented with 10% FBS and humanosteosarcoma cells (HOSC) are cultured in minimal essential mediasupplemented with 10% fetal bovine serum (MEM-10% FBS); all cellincubations are at 37° C. in a humidified environment containing 5% CO₂.

COX-1 Assay

In preparation for the COX-1 assay, THP-1 cells are grown to confluency,split 1:3 into RPMI containing 2% FBS and 10 mM phorbol 12-myristate13-acetate (TPA), and incubated for 48 h on a shaker to preventattachment. Cells are pelleted and resuspended in Hank's Buffered Saline(HBS) at a concentration of 2.5×10⁶ cells/mL and plated in 96-wellculture plates at a density of 5×10⁵ cells/mL. Test compounds arediluted in HBS and added to the desired final concentration and thecells are incubated for an additional 4 hours. Arachidonic acid is addedto a final concentration of 30 mM, the cells incubated for 20 minutes at37° C., and enzyme activity determined as described below.

COX-2 Assay

For the COX-2 assay, subconfluent HOSC are trypsinized and resuspendedat 3×10⁶ cells/mL in MEM-FBS containing 1 ng human IL-1b/mL, plated in96-well tissue culture plates at a density of 3×10⁴ cells per well,incubated on a shaker for 1 hour to evenly distribute cells, followed byan additional 2 hour static incubation to allow attachment. The media isthen replaced with MEM containing 2% FBS (MEM-2% FBS) and 1 ng humanIL-1b/mL, and the cells incubated for 18-22 hours. Following replacementof media with 190 mL MEM, 10 mL of test compound diluted in HBS is addedto achieve the desired concentration and the cells incubated for 4hours. The supernatants are removed and replaced with MEM containing 30mM arachidonic acid, the cells incubated for 20 minutes at 37° C., andenzyme activity determined as described below.

COX Activity Determined

After incubation with arachidonic acid, the reactions are stopped by theaddition of 1N HCl, followed by neutralization with 1N NaOH andcentrifugation to pellet cell debris. Cyclooxygenase enzyme activity inboth HOSC and THP-1 cell supernatants is determined by measuring theconcentration of PGE₂ using a commercially available ELISA (Neogen#404110). A standard curve of PGE₂ is used for calibration, andcommercially available COX-1 and COX-2 inhibitors are included asstandard controls.

Raf Kinase Assay

In vitro Raf kinase activity is measured by the extent ofphosphorylation of the substrate MEK (Map kinase/ERK kinase) byactivated Raf kinase, as described in GB 1,238,959 (incorporated hereinby reference in its entirety). Phosphorylated MEK is trapped on a filterand incorporation of radiolabeled phosphate is quantified byscintillation counting.

Materials:

Activated Raf is produced by triple transfection of Sf9 cells withbaculoviruses expressing “Glu-Glu”-epitope tagged Raf,val¹²-H-Ras, andLck. The “Glu-Glu”-epitope, Glu-Try-Met-Pro-Met-Glu, was fused to thecarboxy-terminus of full length c-Raf.

Catalytically inactive MEK (K97A mutation) is produced in Sf9 cellstransfected with a baculovirus expressing c-terminus “Glu-Glu”epitope-tagged K97A MEK1.

Anti “Glu-Glu” antibody was purified from cells grown as described in:Grussenmeyer, et al., Proceedings of the National Academy of Science,U.S.A. pp 7952-7954, 1985.

Column buffer: 20 mM Tris pH 8, 100 mM NaCl, 1 mM EDTA, 2.5 mM EGTA, 10mM MgCl₂, 2 mM DTT, 0.4 mM AEBSF, 0.1% n-octylglucopyranoside, 1 nMokadeic acid, and 10 μg/mL each of benzamidine, leupeptin, pepstatin,and aprotinin.

5× Reaction buffer: 125 mM HEPES pH=8, 25 mM MgCl₂, 5 mM EDTA, 5 mMNa₃VO₄, 100 μg/mL BSA.

Enzyme dilution buffer: 25 mM HEPES pH 8, 1 mM EDTA, 1 mM Na₃VO₄, 400μg/mL BSA.

Stop solution: 100 mM EDTA, 80 mM sodium pyrophosphate.

Filter plates: Milipore multiscreen #SE3MO78E3, Immobilon-P (PVDF).

Methods:

Protein purification: Sf9 cells were infected with baculovirus and grownas described in Williams, et al., Proceedings of the National Academy ofScience, U.S.A. pp 2922-2926, 1992. All subsequent steps were preformedon ice or at 4° C. Cells were pelleted and lysed by sonication in columnbuffer. Lysates were spun at 17,000×g for 20 min, followed by 0.22 μmfiltration. Epitope tagged proteins were purified by chromatography overGammaBind Plus affinity column to which the “Glu-Glu” antibody wascoupled. Proteins were loaded on the column followed by sequentialwashes with two column volumes of column buffer, and eluted with 50μg/mL Glu-Tyr-Met-Pro-Met-Glu in column buffer.Raf kinase assay: Test compounds were evaluated using ten 3-fold serialdilutions starting at 10-100 μM. 10 μL of the test inhibitor or control,dissolved in 10% DMSO, was added to the assay plate followed by theaddition of 30 μL of the a mixture containing 10 μL 5× reaction buffer,1 mM ³³P-γ-ATP (20 μCi/mL), 0.5 μL MEK (2.5 mg/mL), 1 μL 50 mMβ-mercaptoethanol. The reaction was started by the addition of 10 μL ofenzyme dilution buffer containing 1 mM DTT and an amount of activatedRaf that produces linear kinetics over the reaction time course. Thereaction was mixed and incubated at room temperature for 90 min andstopped by the addition of 50 μL stop solution. 90 μL aliquots of thisstopped solution were transferred onto GFP-30 cellulose microtiterfilter plates (Polyfiltronics), the filter plates washed in four wellvolumes of 5% phosphoric acid, allowed to dry, and then replenished with25 μL scintillation cocktail. The plates were counted for ³³P gammaemission using a TopCount Scintillation Reader.

While the compounds of the invention can be administered as the soleactive pharmaceutical agent, they can also be used in combination withone or more compounds of the invention or other agents. Whenadministered as a combination, the therapeutic agents can be formulatedas separate compositions that are given at the same time or differenttimes, or the therapeutic agents can be given as a single composition.

The foregoing is merely illustrative of the invention and is notintended to limit the invention to the disclosed compounds. Variationsand changes which are obvious to one skilled in the art are intended tobe within the scope and nature of the invention which are defined in theappended claims.

From the foregoing description, one skilled in the art can easilyascertain the essential characteristics of this invention, and withoutdeparting from the spirit and scope thereof, can make various changesand modifications of the invention to adapt it to various usages andconditions.

For the treatment of TNF-α, IL-1β, IL-6, and IL-8 mediated diseases,cancer, and/or hyperglycemia, the compounds of the present invention maybe administered orally, parentally, by inhalation spray, rectally, ortopically in dosage unit formulations containing conventionalpharmaceutically acceptable carriers, adjuvants, and vehicles. The termparenteral as used herein includes, subcutaneous, intravenous,intramuscular, intrasternal, infusion techniques or intraperitoneally.

Treatment of diseases and disorders herein is intended to also includethe prophylactic administration of a compound of the invention, apharmaceutical salt thereof, or a pharmaceutical composition of eitherto a subject (i.e., an animal, preferably a mammal, most preferably ahuman) believed to be in need of preventative treatment, such as, forexample, pain, inflammation and the like.

The dosage regimen for treating a TNF-α, IL-1, IL-6, and IL-8 mediateddiseases, cancer, and/or hyperglycemia with the compounds of thisinvention and/or compositions of this invention is based on a variety offactors, including the type of disease, the age, weight, sex, medicalcondition of the patient, the severity of the condition, the route ofadministration, and the particular compound employed. Thus, the dosageregimen may vary widely, but can be determined routinely using standardmethods. Dosage levels of the order from about 0.01 mg to 30 mg perkilogram of body weight per day, preferably from about 0.1 mg to 10mg/kg, more preferably from about 0.25 mg to 1 mg/kg are useful for allmethods of use disclosed herein.

The pharmaceutically active compounds of this invention can be processedin accordance with conventional methods of pharmacy to produce medicinalagents for administration to patients, including humans and othermammals.

For oral administration, the pharmaceutical composition may be in theform of, for example, a capsule, a tablet, a suspension, or liquid. Thepharmaceutical composition is preferably made in the form of a dosageunit containing a given amount of the active ingredient. For example,these may contain an amount of active ingredient from about 1 to 2000mg, preferably from about 1 to 500 mg, more preferably from about 5 to150 mg. A suitable daily dose for a human or other mammal may varywidely depending on the condition of the patient and other factors, but,once again, can be determined using routine methods.

The active ingredient may also be administered by injection as acomposition with suitable carriers including saline, dextrose, or water.The daily parenteral dosage regimen will be from about 0.1 to about 30mg/kg of total body weight, preferably from about 0.1 to about 10 mg/kg,and more preferably from about 0.25 mg to 1 mg/kg.

Injectable preparations, such as sterile injectable aqueous oroleaginous suspensions, may be formulated according to the known areusing suitable dispersing or wetting agents and suspending agents. Thesterile injectable preparation may also be a sterile injectable solutionor suspension in a non-toxic parenterally acceptable diluent or solvent,for example as a solution in 1,3-butanediol. Among the acceptablevehicles and solvents that may be employed are water, Ringer's solution,and isotonic sodium chloride solution. In addition, sterile, fixed oilsare conventionally employed as a solvent or suspending medium. For thispurpose any bland fixed oil may be employed, including synthetic mono-or diglycerides. In addition, fatty acids such as oleic acid find use inthe preparation of injectables.

Suppositories for rectal administration of the drug can be prepared bymixing the drug with a suitable non-irritating excipient such as cocoabutter and polyethylene glycols that are solid at ordinary temperaturesbut liquid at the rectal temperature and will therefore melt in therectum and release the drug.

A suitable topical dose of active ingredient of a compound of theinvention is 0.1 mg to 150 mg administered one to four, preferably oneor two times daily. For topical administration, the active ingredientmay comprise from 0.001% to 10% w/w, e.g., from 1% to 2% by weight ofthe formulation, although it may comprise as much as 10% w/w, butpreferably not more than 5% w/w, and more preferably from 0.1% to 1% ofthe formulation.

Formulations suitable for topical administration include liquid orsemi-liquid preparations suitable for penetration through the skin(e.g., liniments, lotions, ointments, creams, or pastes) and dropssuitable for administration to the eye, ear, or nose.

For administration, the compounds of this invention are ordinarilycombined with one or more adjuvants appropriate for the indicated routeof administration. The compounds may be admixed with lactose, sucrose,starch powder, cellulose esters of alkanoic acids, stearic acid, talc,magnesium stearate, magnesium oxide, sodium and calcium salts ofphosphoric and sulphuric acids, acacia, gelatin, sodium alginate,polyvinyl-pyrrolidine, and/or polyvinyl alcohol, and tableted orencapsulated for conventional administration. Alternatively, thecompounds of this invention may be dissolved in saline, water,polyethylene glycol, propylene glycol, ethanol, corn oil, peanut oil,cottonseed oil, sesame oil, tragacanth gum, and/or various buffers.Other adjuvants and modes of administration are well known in thepharmaceutical art. The carrier or diluent may include time delaymaterial, such as glyceryl monostearate or glyceryl distearate alone orwith a wax, or other materials well known in the art.

The pharmaceutical compositions may be made up in a solid form(including granules, powders or suppositories) or in a liquid form(e.g., solutions, suspensions, or emulsions). The pharmaceuticalcompositions may be subjected to conventional pharmaceutical operationssuch as sterilization and/or may contain conventional adjuvants, such aspreservatives, stabilizers, wetting agents, emulsifiers, buffers etc.

Solid dosage forms for oral administration may include capsules,tablets, pills, powders, and granules. In such solid dosage forms, theactive compound may be admixed with at least one inert diluent such assucrose, lactose, or starch. Such dosage forms may also comprise, as innormal practice, additional substances other than inert diluents, e.g.,lubricating agents such as magnesium stearate. In the case of capsules,tablets, and pills, the dosage forms may also comprise buffering agents.Tablets and pills can additionally be prepared with enteric coatings.

Liquid dosage forms for oral administration may include pharmaceuticallyacceptable emulsions, solutions, suspensions, syrups, and elixirscontaining inert diluents commonly used in the art, such as water. Suchcompositions may also comprise adjuvants, such as wetting, sweetening,flavoring, and perfuming agents.

1. A compound of formula

or a pharmaceutically acceptable salt thereof, wherein R¹ is H or C₁₋₈alkyl; R² is C₁₋₈alkyl, phenyl, benzyl, R^(c), R^(f), C₁₋₄alkylR^(c), C₁₋₄alkylR^(f) or R^(g); R³ is phenyl, or naphthyl, any of which are substituted by 0, 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a); R⁴ is unsaturated 6-membered ring heterocycle containing only one N atom as heteroatom substituted by 0, 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a); R^(a) is independently at each instance H or R^(b); R^(b) is independently at each instance C₁₋₈alkyl, phenyl or benzyl; R^(c) is independently at each instance a saturated or unsaturated 5-, 6- or 7-membered monocyclic or 6-, 7-, 8-, 9-, 10- or 11-membered bicyclic ring containing 1, 2 or 3 atoms selected from N, O and S, wherein the ring is fused with 0 or 1 benzo groups and 0 or 1 saturated or unsaturated 5-, 6- or 7-membered heterocyclic ring containing 1, 2 or 3 atoms selected from N, O and S; wherein the carbon atoms of the ring are substituted by 0, 1 or 2 oxo groups; R^(d) is independently at each instance C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) or —NR^(a)C₂₋₆alkylOR^(a); R^(e) is independently at each instance C₁₋₆alkyl substituted by 1, 2 or 3 substituents independently selected from R^(d); R^(f) is independently at each instance R^(c) substituted by 1, 2 or 3 substituents independently selected from R^(d); and R^(g) is independently at each instance R^(b) substituted by 1, 2 or 3 substituents independently selected from R^(c), R^(f) and R^(d).
 2. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is H.
 3. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R¹ is C₁₋₈alkyl.
 4. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R² is R^(c), R^(f), C₁₋₄alkylR^(c), C₁₋₄alkylR^(f) or R^(g).
 5. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R² is C₁₋₈alkyl, phenyl or benzyl.
 6. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R³ is unsubstituted naphthyl or phenyl substituted by 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a).
 7. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein R⁴ is pyridine substituted by 0, 1, 2 or 3 substituents selected from C₁₋₈alkyl, C₁₋₄haloalkyl, halo, cyano, nitro, —C(═O)R^(b), —C(═O)OR^(b), —C(═O)NR^(a)R^(a), —C(═NR^(a))NR^(a)R^(a), —OR^(a), —OC(═O)R^(b), —OC(═O)NR^(a)R^(a), —OC(═O)N(R^(a))S(═O)₂R^(b), —OC₂₋₆alkylNR^(a)R^(a), —OC₂₋₆alkylOR^(a), —SR^(a), —S(═O)R^(b), —S(═O)₂R^(b), —S(═O)₂NR^(a)R^(a), —S(═O)₂N(R^(a))C(═O)R^(b), —S(═O)₂N(R^(a))C(═O)OR^(b), —S(═O)₂N(R^(a))C(═O)NR^(a)R^(a), —NR^(a)R^(a), —N(R^(a))C(═O)R^(b), —N(R^(a))C(═O)OR^(b), —N(R^(a))C(═O)NR^(a)R^(a), —N(R^(a))C(═NR^(a))NR^(a)R^(a), —N(R^(a))S(═O)₂R^(b), —N(R^(a))S(═O)₂NR^(a)R^(a), —NR^(a)C₂₋₆alkylNR^(a)R^(a) and —NR^(a)C₂₋₆alkylOR^(a).
 8. The compound of claim 1 or a pharmaceutically acceptable salt thereof, wherein the compound is: 4-(4-chloro-phenyl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chloro-phenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chloro-phenyl)-1-piperidin-3-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chloro-phenyl)-1-piperidin-4-ylmethyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chloro-phenyl)-1-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(3,4-dichlorophenyl)-1-piperidin-4-yl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chlorophenyl)-1-(1-methyl-piperidin-4-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chlorophenyl)-1-(1-methyl-piperidin-3-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(4-chlorophenyl)-1-(1-isopropyl-piperidin-4-yl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-[4-(4-chlorophenyl)-3-methoxy-5-pyridin-4-yl-pyrazol-1-yl]-piperidine; 4-(3,4-dichloro-phenyl)-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(3,4-dichloro-phenyl)-1-isopropyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(3,4-dichloro-phenyl)-1-isopropyl-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1-pyridin-3-ylmethyl-1,2-dihydro-pyrazol-3-one; 1-cyclohexylmethyl-4-(3,4-dichloro-phenyl)-2-methyl-5-pyridin-4-yl-1,2-dihydro-pyrazol-3-one; 1-(4-aminocyclohexyl)-4-(4-chlorophenyl)-5-pyridin-4-yl-1,2-dihydropyrazol-3-one; 1-(4-aminocyclohexyl)-4-napthalen-2-yl-5-pyridin-4-yl-1,2-dihydropyrazol-3-one; or 4-naphthalen-2-yl-1-(3-phenylpropyl)-5-pyridin-4-1,2-dihydropyrazol-3-one.
 9. A pharmaceutical composition comprising a compound according to claim 1 and a pharmaceutically acceptable carrier or diluent. 